Levobunolol hydrochloride is a class of non-selective β-receptor blocker with good therapeutic effects on open-angle glaucoma. It has been listed by the US FDA as the drug of first choice for the treatment of glaucoma. As levobunolol hydrochloride is a chiral drug, its existing synthetic routes include chiral resolution (Chinese Journal of Medicinal Chemistry, 2010, 20, 1, 32) or direct asymmetric synthesis (U.S. Pat. No. 5,426,227A; Chinese Journal of Medicinal Chemistry, 2003, 13, 3, 166). However, preparing levobunolol hydrochloride by the chiral resolution method generally has the problem of low synthesis efficiency after the chiral resolution. The direct asymmetric synthesis of levobunolol hydrochloride usually uses chiral epichlorohydrin as a raw material, where since there are two reaction sites when the epichlorohydrin molecule reacts with a nucleophilic reagent (positions 1 and 3, for the racemic epichlorohydrin, the products obtained by reacting at the positions 1 and 3 are identical; but for the chiral epichlorohydrin, the stereo configurations of the products obtained by reacting at positions 1 and 3 are reversed), there is a problem that the optical purity is difficult to control due to poor regioselectivity.